This menu provides chemical functions relating to structures like molecule cleaning, aromatization, reaction-handling, naming, and more.
| Menu item | Icon | Description | 
|---|---|---|
| Clean 2D > Clean in 2D |  | Calculates new 2D coordinates for the molecule. | 
| Clean 2D > Clean and Arrange in 2D |  | Cleans structures and positions them to the center of the canvas. | 
| Clean 2D > Hydrogenize Chiral Center | N/A | Adds an explicit hydrogen atom to a chiral center having no terminal atoms when 2D cleaning is performed. | 
| Clean 3D |  | Calculates 3D coordinates for the molecule base on the method set in the Preferences > 3D Options dialog. | 
| Directed Merge > Assign Atoms |  | Chooses the atoms of the fragments to be merged. | 
| Directed Merge > Merge |  | Merges the fragments at the atoms set. | 
| Add > Add Explicit Hydrogens |  | Adds explicit H atoms instead of the current implicit ones. Explicit hydrogens are displayed with atoms joining their neighbor while implicit hydrogens are displayed by atom symbols only. | 
| Add > Data |  | Attaches data such as the stoichiometry coefficient to the molecule. | 
| Add > Absolute Stereo (CHIRAL) |  | Sets chiral flag for the molecule. | 
| Add > Multi-Center | N/A | Adds a multi-center attachment point representing a group of atoms. | 
| Add > Position Variation Bond |  | Create a variable point of attachment to represent a connection point to a group of atoms. | 
| Add > No Structure | N/A | Places a No Structure label on the canvas. | 
| Remove > Explicit Hydrogens |  | Removes explicit H atoms and increases the number of implicit hydrogens. | 
| Remove > Data | N/A | Removes the attached data from the molecule. | 
| Remove > Absolute Stereo (CHIRAL) |  | Removes the chiral flag of the molecule. | 
| Edit data | N/A | Changes a previously attached data such as the stoichiometry coefficient of the molecule. | 
| Edit properties | N/A | Bond properties can be edited from this menu. | 
| Aromatic Form > Convert to Aromatic Form |  | Transforms the molecule to aromatic representation using the transformation method set. | 
| Aromatic Form > Conversion Method > Basic | N/A | The basic aromatization method is described here. | 
| Aromatic Form > Conversion Method > General | N/A | The general aromatization method is described here. | 
| Aromatic Form > Conversion Method > Loose | N/A | The loose aromatization method is described here. | 
| Aromatic Form > Convert to Kekulé Form |  | Transforms the molecule to non-aromatic representation. | 
| Group > Group |  | Creates a custom Substructure Group (S-group). | 
| Group > Frequency Variation |  | Creates a Repeating Unit with Repetition Ranges. | 
| Group > Merge Brackets | N/A | Creates a bracket that crosses two bonds. | 
| Group > Edit Group | N/A | Modifies the properties of the selected group. | 
| Group > Contract Group | N/A | Contracts all groups to their abbreviations. | 
| Group > Expand Group | N/A | Displays the full structure instead of the abbreviations. | 
| Group > Ungroup | N/A | Removes all abbreviated group associations from the molecule. | 
| Reaction > Merge Reactants | N/A | Merges the selected fragments to a reactant, product, or agent. | 
| Reaction > Unmerge Reactants | N/A | Removes selected fragments from a previously merged reactant, product, or agent. | 
| Mapping > Map Atoms |  | Inserts map numbers of the selected atoms. | 
| Mapping > Manual Atom Map |  | Inserts map numbers manually. | 
| Mapping > Reaction Mapping Method > Complete | N/A | All atoms in the reaction are mapped. | 
| Mapping > Reaction Mapping Method > Changing | N/A | Only those atoms are mapped that have changing bond. Either the bond order changes, a new bond is created, or the bond is deleted. Orphan and widow atoms are included. | 
| Mapping > Reaction Mapping Method > Matching | N/A | Maps all matching atoms in the reaction (Daylight style mapping). A reaction atom is called matching if it is not an orphan/widow atom: it exists on both sides of the reaction. | 
| Mapping > Unmap Atoms |  | Removes map numbers of the selected atoms. | 
| R-Logic | N/A | Allows setting additional R-group conditions such as occurrence, rest H, and if-then expressions to R-groups in the R-logic dialog window. | 
| Place Analysis Box | N/A | Places the Analysis Box containing the preset calculations. | 
| Structure to Name | N/A | Generates IUPAC and/or Traditional Name and/or displays CAS Registry Numbers®. | 
| Name to Structure | N/A | Opens the Source window in IUPAC Name format, and enables you to enter directly an IUPAC Name and convert it to structure. | 
| Markush Enumeration | N/A | Generates a whole or a subset of the library of a generic Markush Structure. | 
| Check Structure |  | Checks and corrects chemical structures. See Structure Checker for more information. | 
| Auto Check | N/A | Toggles auto checking of structures while drawing. |